Composite part and metal part nesting connection process based on glue injection in gap

Abstract

The invention discloses a nested connection process for a composite material part and a metal part based on glue injection in a gap, and solves the problems that a stress concentration effect is generated at the joint of the composite material part and the metal part by adopting a traditional mechanical connection mode, cracks of the composite material are easily caused at the stress concentration position under the action of external force, and the service life of the composite material part is prolonged. And therefore, the connecting strength of the composite material and the metal piece is low. The composite material piece and the metal piece are connected through the adhesive, stress at the connecting position can be smoothed, and the problem that stress concentration is generated at the connecting position is avoided; according to the invention, a glue injection hole is formed in an external assembly, an adhesive is injected into a gap between the composite material piece and the metal piece through the glue injection hole, and gas in the gap between the composite material piece and the metal piece can be exhausted by setting the glue injection direction of glue injection, so that the connection uniformity is improved.

Description

TECHNICAL FIELD

[0001] The application relates to a composite material piece and metal piece connecting method, in particular to a composite material piece and metal piece nesting connecting process based on gap internal glue injection. BACKGROUND

[0002] Composite materials (especially C / SiC composite materials) have the advantages of light weight, high strength, corrosion resistance and the like, and are widely applied in the fields of aviation, aerospace, automobiles and the like. In particular in the field of aerospace, light structure support pieces are usually designed in the form of composite material and metal fusion to realize high-precision connection of a connecting surface. However, the composite material and the metal have significant differences in physical and chemical properties, which leads to the mismatch of mechanical properties of the two, and the connecting mode is relatively more complex.

[0003] The traditional mechanical connecting mode (such as drilling screw connection) can cause stress concentration effect at the connecting position, and under the action of external force, cracks of the composite material are easily caused at the stress concentration position, thereby leading to low connecting strength of the composite material and the metal piece. SUMMARY

[0004] The application aims to solve the technical problem that the traditional mechanical connecting mode of the composite material piece and the metal piece can cause stress concentration effect at the connecting position, and under the action of external force, cracks of the composite material are easily caused at the stress concentration position, thereby leading to low connecting strength of the composite material and the metal piece, and provides a composite material piece and metal piece nesting connecting process based on gap internal glue injection.

[0005] In order to achieve the above-mentioned purpose, the application adopts the following technical scheme: A composite material piece and metal piece nesting connecting process based on gap internal glue injection, which is characterized by comprising the following steps: Step 1, according to the assembly requirement, glue injection holes are arranged on the components of the metal piece and the composite material piece which are sleeved outside the rotary body, and the size of the glue injection hole is 1mm-5mm; Step 2, the metal piece and the composite material piece are repaired, cleaned and dried; Step 3, according to the assembly requirement, the metal piece and the composite material piece are assembled; Step 4, a sealing agent is used to seal the gap between the metal piece and the composite material piece; Step 5, glue is injected into the gap between the metal piece and the composite material piece through the glue injection hole, each glue injection hole is sealed and solidified.

[0006] Further, step 1 is specifically: According to the assembly requirement, it is judged that the metal piece and the composite material piece of the rotating body type need to be sleeved with the external assembly. If the assembly sleeved outside is a metal piece, a plurality of glue injection holes are uniformly arranged on the surface of the metal piece. Otherwise, a plurality of glue injection holes are uniformly arranged on the surface of the composite material piece. The size of the glue injection hole is 1mm-5mm.

[0007] Further, in step 1, the size of the glue injection hole is determined according to the thickness of the assembly in which the glue injection hole is arranged. Specifically, When the thickness of the assembly in which the glue injection hole is arranged is 1mm-3mm, the size of the glue injection hole is 1mm-2mm. When the thickness of the assembly in which the glue injection hole is arranged is 3mm-6mm, the size of the glue injection hole is 2mm-3mm. When the thickness of the assembly in which the glue injection hole is arranged is greater than 6mm, the size of the glue injection hole is 3mm-5mm.

[0008] Further, step 2 is specifically: Step 2.1, the metal piece and the composite material piece are repaired so that the circumferential theoretical gap of the metal piece and the composite material piece is 0.1mm-0.2mm. Step 2.2, the surface of the composite material piece is polished with 80-mesh sandpaper, and a dust collector is used for adsorption at the same time. Step 2.3, use a dust-free cloth or a rubber glove to dip saturated alcohol to clean the surface of the composite material piece. Step 2.4, use a high-pressure air gun to clean the surface of the composite material piece and then perform anti-pollution protection. Step 2.5, clean the surface of the metal piece with acetone and then perform anti-pollution protection.

[0009] Further, step 3 is specifically: According to the assembly requirement, the metal piece and the composite material piece are assembled, and a plug gauge or a U-shaped steel wire with the same diameter is used for gap control to ensure that the gap of each side surface of the metal piece and the composite material piece is 0.1mm-0.2mm.

[0010] Further, the sealing agent in step 4 is one or more of the following: plasticine, adhesive tape, and adhesive. Step 4 is specifically: Step 4.1, for the assembled metal piece and the composite material piece, it is judged whether there is a design hole on the internal assembly. If there is, plasticine is used for sealing and filling. Step 4.2, it is judged whether the end surface of the metal piece and the composite material piece is flush. If it is flush, the gap between the metal piece and the composite material piece is sealed with adhesive tape. If it is not flush, the gap between the metal piece and the composite material piece is sealed with adhesive, and it is left to stand for 3h-5h at room temperature.

[0011] Further, step 5 is specifically: Step 5.1, selecting the glue injection direction according to the shape of the metal piece and the composite material piece; Step 5.2, sequentially injecting glue into the glue injection hole according to the selected glue injection direction; Step 5.3, sealing each glue injection hole after glue injection with adhesive tape, and curing the composite material piece and the metal piece at room temperature for 48-50 hours.

[0012] Further, step 5.1 is specifically: Determine the shape of the metal piece and the composite material piece, if it is a cylindrical pipe, place the metal piece and the composite material piece horizontally, and move from any middle glue injection hole to both ends in any direction along the circumference; or place the metal piece and the composite material piece vertically, and move from any surface to the glue injection hole at the lower end to the glue injection hole at the upper end; If it is a square column pipe, place the metal piece and the composite material piece horizontally, and the moving direction of the glue injection surface is: lower bottom surface, left side surface, right side surface, upper surface, or lower bottom surface, right side surface, left side surface, upper surface; The moving direction of the lower bottom surface and the upper surface is: moving from the middle glue injection hole to both ends on each glue injection surface; The moving direction of the left side surface and the right side surface is: first horizontally, moving from the middle glue injection hole to the glue injection hole at both ends, and then vertically, moving from the glue injection hole at the lower end to the glue injection hole at the upper end.

[0013] Further, in step 5.2, when injecting glue, observe whether the glue injection hole has glue overflow, if it does, stop injecting glue and continue injecting glue with another glue injection hole.

[0014] Further, in step 5.2, the glue injected into the glue injection hole is J-133 or epoxy resin glue.

[0015] Advantages of the present application: 1. The present application provides a composite material piece and metal piece nesting connection process based on gap glue injection, which connects the composite material piece and the metal piece with adhesive, can gently connect the stress, and avoids the problem of stress concentration at the connection.

[0016] 2. The present application provides a composite material piece and metal piece nesting connection process based on gap glue injection, which opens glue injection holes on the external assembly, injects adhesive into the gap between the composite material piece and the metal piece through the glue injection hole, and can discharge the gas in the gap between the composite material piece and the metal piece by setting the glue injection direction, improving the uniformity of the connection.

[0017] 3. The present application provides a composite material piece and metal piece nesting connection process based on gap glue injection, which also has the characteristics of good sealing and simple operation. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece are square column pipe and metal piece is nested in the outside schematic diagram; Figure 2 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece are circular column pipe and composite material piece is nested in the outside schematic diagram; Figure 3 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece are square column pipe and circular column pipe, gap control schematic diagram; (a) metal piece and composite material piece are square column pipe;(b) metal piece and composite material piece are circular column pipe; Figure 4 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece end face flush assembly effect drawing; (a) metal piece and composite material piece are square column pipe;(b) metal piece and composite material piece are circular column pipe; Figure 5 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece end face not flush assembly effect drawing; (a) metal piece and composite material piece are square column pipe;(b) metal piece and composite material piece are circular column pipe; Figure 6 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece are square column pipe, the injection direction setting schematic diagram on top; Figure 7 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, metal piece and composite material piece are square column pipe, left side injection process intent; Figure 8 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, according to the injection direction of Figure 6 obtained injection diffusion area chart; Figure 9 is a kind of based on gap inner glue injection composite material piece and metal piece nesting connection process embodiment of the present application, according to the injection direction of Figure 7 obtained injection diffusion area chart; Figure 10It is an embodiment of the present application that the metal part and the composite material part are both cylindrical pipes, and the diffusion area of the injected glue is obtained by vertical placement.

[0019] The reference signs are as follows: 1-metal part, 2-composite material part, 3-injection hole, 4-design hole, 5-upper surface of injection surface, 6-left surface of injection surface, 7-end surface of metal part, 8-end surface of composite material part, 9-plug ruler, 10-equal-diameter U-shaped steel wire. DETAILED DESCRIPTION

[0020] The technical solutions of the present application will be described clearly and completely in combination with the drawings and embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0021] The embodiment of the present application provides a uniform gap connection method for a rotary body type composite material part 2 and a metal part 1, and the glue and injection tool used are: The glue is selected according to actual needs, such as J-133, epoxy resin glue, etc. The injection tool is an injection gun, a syringe, an injection machine, etc.

[0022] For a small-diameter injection hole 3 and a small injection range, a syringe can be selected for glue injection; for a large-diameter and a large injection area, an injection gun or an injection machine can be selected.

[0023] A uniform gap connection method for a rotary body type composite material part 2 and a metal part 1 includes the following steps: Step 1: According to the assembly requirement, it is judged that the metal part 1 and the composite material part 2 of the rotary body type need to be sleeved with the external assembly. If the assembly sleeved on the outside is the metal part 1, a plurality of injection holes 3 are uniformly arranged on the surface of the metal part 1. Otherwise, a plurality of injection holes 3 are uniformly arranged on the surface of the composite material part 2. The size of the injection hole 3 is 1mm-5mm. In this embodiment 1, the injection hole 3 is designed to allow the glue to be smoothly injected into the gap between the composite material part 2 and the metal part 1. The size, shape and distribution of the injection hole 3 directly affect the later injection effect, so as to achieve the expected injection effect.

[0024] The thicker the plate is, the larger the size of the injection hole 3 needs to be, so as to ensure that the glue can penetrate to the bonding surface of the composite material and the metal.

[0025] The size of the injection hole 3 is determined according to the thickness of the assembly in which the injection hole 3 is arranged, and specifically: When the thickness of the component with the glue injection hole 3 is 1mm ~3mm, the size of the glue injection hole 3 is 1mm ~2mm; when the thickness of the component with the glue injection hole 3 is 3mm ~6mm, the size of the glue injection hole 3 is 2mm ~3mm; when the thickness of the component with the glue injection hole 3 is greater than 6mm, the size of the glue injection hole 3 is 3mm ~5mm.

[0026] The smaller glue injection hole 3 is suitable for precise glue injection, which can ensure that the glue is accurately injected into the specified position, but the injection speed is slower; while the larger glue injection hole 3 is suitable for large and fast glue injection, but it may cause uneven distribution of glue.

[0027] The shape of the glue injection hole 3 should be designed according to the requirements to ensure that the glue can be smoothly injected into the specified position. Common shapes of the glue injection hole 3 include circular, oval, square, etc.

[0028] The distribution and layout of the glue injection hole 3 should be reasonably planned according to the structure of the product and the glue injection requirements, so as to improve the uniformity and injection efficiency of the glue.

[0029] Step 2, repair the metal part 1 and the composite material part 2, so that the circumferential gap between the metal part 1 and the composite material part 2 is 0.1mm ~0.2mm; use 80 mesh sandpaper to polish the surface of the composite material part 2, and use a dust collector to adsorb; the adsorption time of each surface is not less than 2 minutes. No visible particles, burrs and other excess materials are allowed; use a dust-free cloth or rubber gloves to dip saturated alcohol to clean the surface of the composite material part 2, and dry it; use a high-pressure air gun to clean the surface of the composite material part 2 and then protect it from pollution; the cleaning time of each surface is not less than 1 minute; clean the surface of the metal part 1 with acetone to ensure that the surface is free of oil stains, foreign matter, etc.; then perform anti-pollution protection.

[0030] Step 3, according to the assembly requirements, assemble the metal part 1 and the composite material part 2, as shown in Figure 1 , which is a schematic diagram of the metal part 1 and the composite material part 2 being square column pipes and the metal part 1 being sleeved outside, and the metal part 1 and the composite material belonging to plane contact. As shown in Figure 2 , which is a schematic diagram of the metal part 1 and the composite material part 2 being cylindrical pipes and the composite material being sleeved outside, and the metal part 1 and the composite material belonging to curved surface contact. When the metal part 1 and the composite material part 2 are both square column pipes, use a plug gauge 9 to control the gap, so that the gap between the metal part 1 and the composite material part 2 on each side is 0.1mm ~0.2mm; when the metal part 1 and the composite material part 2 are both cylindrical pipes, use an equal-diameter U-shaped steel wire 10 to control the gap, as shown in Figure 3 (a) and (b).

[0031] Step 4, seal the gap between the metal piece 1 and the composite material piece 2 with a sealant, which is one or more of the following: putty, tape, adhesive; Specifically: Step 4.1, for the assembled metal piece 1 and the composite material piece 2, determine whether there are design holes 4 on the internal components, if so, use putty to seal and fill; Step 4.2, determine whether the end surface 7 of the metal piece 1 and the end surface 8 of the composite material piece 2 are flush; as Figure 4 (a) and (b) shown, if flush, use tape to seal the gap between the metal piece 1 and the composite material piece 2; as Figure 5 (a) and (b) shown, if not flush, use adhesive to seal the gap between the metal piece 1 and the composite material piece 2, and stand still at room temperature for 3-5 hours, or choose tape to seal.

[0032] Step 5, inject glue into the gap between the metal piece 1 and the composite material piece 2 through the glue injection hole 3, seal each glue injection hole 3 after injection, and solidify. Specifically: Step 5.1, select the glue injection direction according to the shape of the metal piece 1 and the composite material piece 2; Specifically: Determine the shape of the metal piece 1 and the composite material piece 2, if it is a cylindrical pipe, place the metal piece 1 and the composite material piece 2 horizontally, start from any middle glue injection hole 3 and move to both ends along the circumferential direction in any direction; or, place the metal piece 1 and the composite material piece 2 vertically, start from any surface and move from the lower end glue injection hole 3 to the upper end glue injection hole 3. If the metal piece 1 and the composite material piece 2 are both square pipes, place the metal piece 1 and the composite material piece 2 horizontally, that is: from the lower bottom surface of the glue injection surface, the left side surface 6 of the glue injection surface, or the right side surface of the glue injection surface, the upper surface 5 of the glue injection surface, or from the lower bottom surface of the glue injection surface, the right side surface of the glue injection surface, the left side surface 6 of the glue injection surface, the upper surface 5 of the glue injection surface.

[0033] The moving direction of the lower bottom surface and the upper surface is: from the middle glue injection hole 3 to both ends on each glue injection surface; as Figure 6 shown is a schematic diagram of the glue injection direction setting of the upper surface. As Figure 6 shown, the upper surface 5 of the glue injection surface is an example of the glue injection hole 3, the priority glue injection should be the most central glue injection hole 3 (red box area), followed by the glue injection hole 3 close to the middle area (blue box area), so that the glue spreads outward from the center.

[0034] The moving direction of the left side and the right side is: first longitudinally, moving from the lower end glue injection hole 3 to the upper end glue injection hole 3 (indicated by the longitudinal arrow in the red box area), and then transversely, moving from the middle glue injection hole to the glue injection hole at both ends (indicated by the horizontal arrow); facilitating the use of gravity to exhaust during glue injection, such as Figure 7 The glue injection direction of the left side is shown.

[0035] Step 5.2, when the metal piece 1 and the composite material piece 2 are both square column tubes, glue injection is performed according to the glue injection direction in step 5.1. Among them, the diffusion area diagram of glue injection according to the glue injection direction on the upper side is shown in Figure 6 Figure 8 Figure 8 Among them, the red dashed box area is the diffusion area of glue injection in the most central glue injection hole 3, and the glue injection sequence is A→B→C→D→E→F→G→H as shown in Figure 8 The blue dashed box area is the diffusion area of glue injection in the glue injection hole 3 close to the middle area. According to the glue injection direction on the left side, Figure 7 The diffusion area diagram of glue injection according to the glue injection direction is shown in Figure 9 The glue injection sequence is A→B→C→D→E→F as shown in Figure 9

[0036] When the metal piece 1 and the composite material piece 2 are both cylindrical tubes, the diffusion area diagram of glue injection obtained by vertical placement is shown in Figure 10 The glue injection sequence is A→B as shown in Figure 10

[0037] During glue injection, it is observed whether the glue injection hole 3 has glue overflow, and if there is overflow, glue injection is stopped and another glue injection hole is selected for continuous glue injection.

[0038] By observing whether the glue injection hole 3 has obvious glue overflow, the glue diffusion position at this time is judged, and then the original position is selected for continuous glue injection or a new glue injection hole is selected for glue injection.

[0039] Step 5.3, using adhesive tape to seal each glue injection hole 3 after glue injection, and curing the composite material piece 2 and the metal piece 1 at room temperature for 48h-50h.

[0040] In the composite material piece and metal piece nesting connection process based on gap glue injection, the composite material piece and the metal piece are connected by using adhesive, which can gently connect the stress and avoid the problem of stress concentration at the connection; at the same time, glue injection holes are opened on the external assembly, and adhesive is injected into the gap between the composite material piece and the metal piece through the glue injection hole, and by setting the glue injection direction, the gas in the gap between the composite material piece and the metal piece can be exhausted, improving the uniformity of the connection; it also has the advantages of good sealing, and by reasonably planning the distribution and layout of the glue injection hole according to the structure of the product and the glue injection demand, the uniformity and injection efficiency of the glue injection can be improved.​​​​

[0041] The above description is merely that of a specific implementation of the present application, but the protection scope of the present application is not limited thereto, any change or replacement within the technical scope disclosed by the present application should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A process for joining a composite part and a metal part based on gap-filling adhesive bonding, characterized in that, The method comprises the following steps: Step 1: According to the assembly requirements, a plurality of glue injection holes are uniformly arranged on the surface of the metal part or the composite part which is to be sleeved on the external assembly, and the size of the glue injection hole is 1mm-5mm; Step 2: The metal part and the composite part are repaired, cleaned and dried; Step 3: According to the assembly requirements, the metal part and the composite part are assembled; Step 4: The sealant is used to seal the gap between the metal part and the composite part; Step 5: The gap between the metal part and the composite part is injected through the glue injection hole, each glue injection hole is sealed, and then solidified.

2. The process for joining a composite part to a metal part based on gap-filling adhesive according to claim 1, wherein Step 1 is specifically: According to the assembly requirements, it is judged that the metal part and the composite part of the rotary body need to be sleeved on the external assembly. If the assembly sleeved on the outside is a metal part, a plurality of glue injection holes are uniformly arranged on the surface of the metal part. Otherwise, a plurality of glue injection holes are uniformly arranged on the surface of the composite part. The size of the glue injection hole is 1mm-5mm.

3. The process for joining a composite part to a metal part by a gap-filling adhesive based nesting connection according to claim 1 or 2, characterized in that, In step 1, the size of the glue injection hole is determined according to the thickness of the assembly in which the glue injection hole is arranged, specifically: When the thickness of the assembly in which the glue injection hole is arranged is 1mm-3mm, the size of the glue injection hole is 1mm-2mm; When the thickness of the assembly in which the glue injection hole is arranged is 3mm-6mm, the size of the glue injection hole is 2mm-3mm; When the thickness of the assembly in which the glue injection hole is arranged is greater than 6mm, the size of the glue injection hole is 3mm-5mm.

4. The process for joining a composite part and a metal part based on gap-filling adhesive according to claim 1, wherein Step 2 is specifically: Step 2.1: The metal part and the composite part are repaired, so that the circumferential theoretical gap of the metal part and the composite part is 0.1mm-0.2mm; Step 2.2: The surface of the composite part is polished with 80-mesh sandpaper, and a dust collector is used for adsorption at the same time; Step 2.3: The surface of the composite part is cleaned with a dust-free cloth or a rubber glove dipped in saturated alcohol; Step 2.4: The surface of the composite part is protected against pollution after being cleaned with a high-pressure air gun; Step 2.5: The surface of the metal part is protected against pollution after being cleaned with acetone.

5. The process for joining a composite part to a metal part based on gap-filling adhesive bonding according to claim 1, wherein Step 3 is specifically: According to the assembly requirements, the metal part and the composite part are assembled, and a plug gauge or a U-shaped steel wire with the same diameter is used for gap control to ensure that the gap of each side surface of the metal part and the composite part is 0.1mm-0.2mm.

6. The process for joining a composite part to a metal part based on gap-filling adhesive bonding according to claim 1, wherein: The sealant in step 4 is one or more of the following: plasticine, adhesive tape and adhesive; Step 4 is specifically: Step 4.1: For the assembled metal part and the composite part, it is judged whether there is a design hole on the internal assembly. If there is, plasticine is used for sealing and filling; Step 4.2: It is judged whether the end surface of the metal part and the composite part is flush. If it is flush, the gap between the metal part and the composite part is sealed with adhesive tape. If it is not flush, the gap between the metal part and the composite part is sealed with adhesive, and is left to stand for 3h-5h at room temperature.

7. The process for joining a composite part and a metal part based on gap-filling adhesive bonding according to claim 1, wherein Step 5 is specifically: Step 5.1: The glue injection direction is selected according to the shape of the metal part and the composite part; Step 5.2: The glue is injected into the glue injection hole in sequence according to the selected glue injection direction; Step 5.3, seal each glue injection hole after glue injection by using adhesive tape, and cure the composite material piece and the metal piece at room temperature for 48-50 hours after glue injection.

8. The process for joining a composite part and a metal part based on gap-filling adhesive according to claim 7, wherein Step 5.1 is specifically: Determine the shape of the metal piece and the composite material piece, if it is a cylindrical pipe, place the metal piece and the composite material piece horizontally, and move from any middle glue injection hole to both ends in any direction along the circumference; or place the metal piece and the composite material piece vertically, and move from any surface to the glue injection hole at the upper end from the glue injection hole at the lower end; If it is a square column pipe, place the metal piece and the composite material piece horizontally, and the moving direction of the glue injection surface is: lower bottom surface, left side surface, right side surface, upper surface, or lower bottom surface, right side surface, left side surface, upper surface; The moving direction of the lower bottom surface and the upper surface is: from the middle glue injection hole to both ends on each glue injection surface; The moving direction of the left side surface and the right side surface is: first move horizontally from the middle glue injection hole to the glue injection hole at both ends, and then move vertically from the glue injection hole at the lower end to the glue injection hole at the upper end.

9. The process for joining a composite part and a metal part based on gap-filling adhesive bonding according to claim 7, wherein: In step 5.2, when glue injection, observe whether the glue injection hole has glue overflow, if it overflows, stop glue injection, and continue glue injection with another glue injection hole.

10. The process for joining a composite part and a metal part based on gap-filling adhesive according to claim 7, wherein: In step 5.2, J-133 or epoxy resin glue is injected into the glue injection hole.

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